Devices and methods for enrichment and alteration of cells and other particles

Abstract

The invention features a device for the deterministic separation of analytes coupled to a reservoir containing a reagent that alters a magnetic propert of the analyte. Exemplary methods include the enrichment of a sample in a desired analyte (e.g., using deterministic separation) or the alteration of a desired analyte in the device. The devices and methods may be advantageously employed to enrich for rare cells, e.g., fetal cells or epithelial cells, present in a sample, e.g., maternal blood.

1 . A device for producing a sample enriched in an analyte, said device comprising: 
 (a) a first channel comprising a structure that deterministically deflects particles having a hydrodynamic size above a critical size in a direction not parallel to the average direction of flow in said structure, wherein said particles are analyte particles or are a non-analyte component of said sample; and    (b) a reservoir fluidly coupled to an output of said first channel through which said analyte passes into said reservoir, wherein said reservoir comprises a reagent that alters a magnetic property of said analyte.    
     
     
         2 . The device of  claim 1 , wherein said first channel is a microfluidic channel.  
     
     
         3 . The device of  claim 1 , wherein said structure comprises an array of obstacles that form a network of gaps, wherein a fluid passing through said gaps is divided unequally into a major flux and a minor flux so that the average direction of the major flux is not parallel to the average direction of fluidic flow in said channel.  
     
     
         4 . The device of  claim 3 , wherein said array of obstacles comprises first and second rows, wherein the second row is displaced laterally relative to the first row so that fluid passing through a gap in the first row is divided unequally into two gaps in the second row.  
     
     
         5 . The device of  claim 1 , wherein said analyte has a hydrodynamic size greater than said critical size.  
     
     
         6 . The device of  claim 1 , wherein said analyte has a hydrodynamic size smaller than said critical size.  
     
     
         7 . The device of  claim 1 , further comprising a magnetic force generator capable of generating a magnetic field.  
     
     
         8 . The device of  claim 7 , wherein said magnetic force generator comprises a region of magnetic obstacles disposed in a second channel.  
     
     
         9 . The device of  claim 8 , wherein at least a portion of said magnetic obstacles comprise a permanent magnet.  
     
     
         10 . The device of  claim 8 , wherein at least a portion of said magnetic obstacles comprise a non-permanent magnet.  
     
     
         11 . The device of  claim 8 , wherein said obstacles are ordered in a two-dimensional array.  
     
     
         12 . The device of  claim 8 , wherein said second channel is a microfluidic channel.  
     
     
         13 . The device of  claim 1 , wherein said reservoir further comprises a second channel comprising a magnet.  
     
     
         14 . The device of  claim 1 , wherein said reagent alters an intrinsic magnetic property of said one or more analytes.  
     
     
         15 . The device of  claim 14 , wherein said reagent comprises sodium nitrite.  
     
     
         16 . The device of  claim 1 , wherein said reagent binds to said one or more analytes.  
     
     
         17 . The device of  claim 16 , wherein said reagent comprises a magnetic particle.  
     
     
         18 . The device of  claim 17 , wherein said magnetic particle comprises an antibody or an antigen-binding fragment thereof.  
     
     
         19 . The device of  claim 18 , wherein said antibody is anti-CD71, anti-CD36, anti-CD45, anti-GPA, anti-antigen i, anti-CD34, or anti-fetal hemoglobin.  
     
     
         20 . The device of  claim 16 , wherein said reagent comprises holo-transferrin.  
     
     
         21 . A method for producing a sample enriched in a first analyte relative to a second analyte, said method comprising: 
 (a) applying at least a portion of said sample to a device comprising a structure that deterministically deflects particles having a hydrodynamic size above a critical size in a direction not parallel to the average direction of flow in said structure, thereby producing a second sample enriched in said first analyte and comprising said second analyte;    (b) combining said second sample with a reagent that alters a magnetic property of said first analyte to produce an altered first analyte; and    (c) applying a magnetic field to said second sample, wherein said magnetic field generates a differential force to physically separate said altered first analyte from said second analyte, thereby producing a sample enriched in said first analyte.    
     
     
         22 . The method of  claim 21 , wherein said reagent binds to said first analyte.  
     
     
         23 . The method of  claim 21 , wherein said reagent alters an intrinsic magnetic property of said first analyte.  
     
     
         24 . The method of  claim 23 , wherein said reagent comprises sodium nitrite.  
     
     
         25 . The method of  claim 21 , wherein said reagent comprises a magnetic particle that binds to or is incorporated into said first analyte.  
     
     
         26 . The method of  claim 25 , wherein said magnetic particle comprises an antibody or an antigen-binding fragment thereof.  
     
     
         27 . The method of  claim 26 , wherein said antibody is anti-CD71, anti-GPA, anti-antigen i, anti-CD45, anti-CD34, or anti-fetal hemoglobin.  
     
     
         28 . The method of  claim 21 , wherein said analyte has a hydrodynamic size greater than said critical size.  
     
     
         29 . The method of  claim 21 , wherein said analyte has a hydrodynamic size smaller than said critical size.  
     
     
         30 . The method of  claim 21 , wherein said sample comprises a maternal blood sample.  
     
     
         31 . The method of  claim 21 , wherein said first analyte is a cell, an organelle, or a virus.  
     
     
         32 . The method of  claim 31 , wherein said cell is a bacterial cell, a fetal cell, or a blood cell.  
     
     
         33 . The method of  claim 32 , wherein said blood cell is a fetal red blood cell.  
     
     
         34 . The method of  claim 31 , wherein said organelle is a nucleus.  
     
     
         35 . A method of producing a sample enriched in red blood cells relative to a second blood component, said method comprising: 
 (a) contacting a sample comprising red blood cells with a reagent that oxidizes iron to produce oxidized hemoglobin; and    (b) applying a magnetic field to said sample, wherein said red blood cells having oxidized hemoglobin are attracted to said magnetic field to a greater extent than said second blood component, thereby producing said sample enriched in said red blood cells.    
     
     
         36 . The method of  claim 35 , wherein said red blood cells are fetal red blood cells.  
     
     
         37 . The method of  claim 36 , wherein said second blood component is a maternal blood cell.  
     
     
         38 . The method of  claim 35 , wherein prior to said step (a), said sample is enriched for said red blood cells.  
     
     
         39 . The method of  claim 38 , wherein said enriching is performed by applying at least a portion of said sample to a device comprising a structure that deterministically deflects particles having a hydrodynamic size above a critical size in a direction not parallel to the average direction of flow in said structure.  
     
     
         40 . The method of  claim 39 , wherein fetal red blood cells are enriched relative to maternal red blood cells.  
     
     
         41 . A device for producing a sample enriched in red blood cells, said device comprising: 
 (a) an analytical device that enriches said red blood cells based on size, shape, deformability, or affinity; and    (b) a reservoir comprising a reagent that oxidizes iron, wherein said reagent increases the magnetic responsiveness of said red blood cells.    
     
     
         42 . The device of  claim 41 , wherein said analytical device comprises a first channel comprising a structure that deterministically deflects particles having a hydrodynamic size above a critical size in a direction not parallel to the average direction of flow in said structure.  
     
     
         43 . The device of  claim 41 , wherein said reagent is sodium nitrite.